CN107406692A - Method for handling the surface and article that include microorganism structure sheaf - Google Patents

Abstract

The present invention provides a kind of method for being used to handle the surface of substrate, and method includes：A) microorganism is made to be grown on the surface of pending substrate to form microorganism structure sheaf, wherein microorganism is selected from fungi, algae, lichens and its any combinations；And microorganism structure b) is coated to form first coating above, wherein first coating has the thickness no more than 1 μm.The present invention also provides a kind of article, including optionally by microorganism structure sheaf made of the method using the present invention.

Description

Method for treating surfaces and articles comprising a microbiological layer

technical field

The present invention relates to a method for treating the surface of a substrate.

The invention also relates to articles comprising a layer of microbial structures.

Background technique

Surface treatments are very common in providing desired surface properties or desired surface topologies. As disclosed in "Self-Assembled Hydrophobic Biofilms"; -&"Biofilms"; -& "Chaplins" September 4, 2014, a bacterium is first used to form a biofilm on a substrate, And then biofilms produce hydrophobins to form hydrophobic surfaces. After that comes the kill switch to kill the bacteria, but the hydrophobin is still there. By this method, the treated surface exhibits hydrophobic properties.

Another approach for surface treatment is biomimicry. It is well recognized that many surfaces in nature can lead to specific behavioral phenomena. Many methods have been developed to mimic the morphology of natural surfaces in order to achieve desired surface properties or topologies.

Water/oil repellency is one of the important properties that can be provided by mimicking the morphology of natural surfaces, and thus has attracted much attention in daily life as well as in many industrial and biological processes. Examples of such natural surfaces include those found on the leaves of some plants (such as lotus leaves), the legs of water striders, and the wings of some insects that exhibit the unusual phenomenon of superhydrophobicity. A famous example is the lotus leaf, which was discovered long ago to be superhydrophobic. These surfaces are characterized in that they often have a binary structure on the micro- and nanoscale, which results in large water contact angles. This is because air can be trapped between the water droplet and the wax crystals at the surface, which minimizes the actual contact area of the water droplet with the surface. Applications of water/oil repellant properties include, for example, reduction of frictional drag on ship hulls, anti-icing and self-cleaning surfaces. As for transparent hydrophobic surfaces, the range of possible applications can be extended to glass-based substrates such as goggles or windshields.

Artificial superhydrophobic surfaces with water contact angles greater than 150° have been prepared by replicating the surface topology of natural superhydrophobic surfaces by various processing techniques such as etching and machining. A number of artificial superhydrophobic surfaces have been studied, also their wetting kinetics as well as their chemical, mechanical and thermal stability, opening up many applications in industrial and biological processes. However, many of the current processing techniques for fabricating artificial superhydrophobic surfaces are difficult and typically use expensive materials or harsh conditions. Together with poor stability and short lifetime, these issues greatly limit the applications of artificial superhydrophobic surfaces.

Therefore, there is a need to develop simple, low-cost methods for surface treatment by mimicking the morphology of natural surfaces. There is also a need to provide robust superhydrophobic/superoleophobic surfaces in a convenient manner.

Contents of the invention

In a first aspect, the invention relates to a method for treating a surface of a substrate, the method comprising:

a) allowing microorganisms to grow on the surface of the substrate to be treated to form a layer of microbial structures, wherein the microorganisms are selected from the group consisting of fungi, bacteria, algae, lichens, and any combination thereof; and

b) coating the microbial structure to form a first coating thereon, wherein the first coating has a thickness of not more than 1 μm.

In a second aspect, the present invention relates to an article comprising a substrate, a layer of microbial structures formed on at least a portion of the surface of the substrate, and a first coating formed on the microbial structures, wherein the microbial structures comprise microorganisms derived from fungi, bacteria, structures of algae, lichens, and any combination thereof; and wherein the first coating has a thickness of not more than 1 μm.

Description of drawings

The following figures are provided for the purpose of illustrating the invention without any intention of limiting the invention.

Figure 1 is a schematic depiction of an article comprising a surface treated by the method of the present invention.

Figures 2a and 2b illustrate, at different magnifications, water droplets on the surface of Streptomyces albicans cultured on the surface of a glass Petri dish according to an embodiment of the present invention.

Figures 3a, 3b and 3c illustrate, at different magnifications, water droplets on the surface of a hydrophobic coating obtained according to an embodiment of the invention.

Figures 4a to 4d illustrate the peel test, wherein Figure 4a shows the tape used to peel off the superhydrophobic coating and the peeling area of the superhydrophobic coating (marked in the rectangle) in the peel test, and Figures 4b, 4c and Figure 4d show the state of water droplets on the surface of the superhydrophobic coating after 1, 5 and 10 peeling operations, respectively.

Figure 5a shows the sample preparation of a superhydrophobic coating obtained according to an example of the present invention for scanning electron microscopy (SEM) analysis. Figure 5b and Figure 5c show the obtained SEM images of the surface of the superhydrophobic coating at different magnifications.

detailed description

While the invention will be described with respect to particular embodiments, this description should not be construed in a limiting sense.

As used in this specification and the appended claims, the singular forms "a" and "an" also include their respective plurals unless the context clearly dictates otherwise.

In the context of the present invention, the terms "about" and "approximately" denote an interval that a person skilled in the art will understand and still ensure the accuracy of the technical effect of the feature in question. The term typically indicates a deviation from the indicated value of ±20%, preferably ±15%, more preferably ±10% and even more preferably ±5% or even ±1%.

It should be understood that the term "comprising" is not limiting. For the purposes of the present invention, the term "consisting of" is considered to be a preferred embodiment of the term "comprising". If a group is defined hereinafter to comprise at least a certain number of embodiments, this means that groups which preferably consist only of these embodiments are also covered.

Furthermore, the terms "first", "second", "third" or "(a)", "(b)", "(c) etc. and the like in the description and claims are used to refer to similar elements and are not necessarily used to describe sequential or chronological order. It should be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein can be described in terms of Operate in a sequence other than that described or illustrated.

Where the terms "first", "second", "third" or "(a)", "(b)", "(c) etc. refer to a step of a method or use, there is no time or Continuity of time intervals, i.e., steps may be performed simultaneously or there may be intervals of seconds, minutes, hours, days, weeks, months or even years between such steps, unless above or Otherwise indicated in the application as set forth herein below.

The object of the present invention is to provide a simple and low-cost method for surface treatment by mimicking the morphology of natural surfaces. One of the advantages of the invention is that the artificial surfaces obtained by the method of the invention are robust and stable.

According to the invention, microorganisms are used for surface treatment. Despite the fact that the growth of microorganisms on surfaces is generally undesirable and tends to prevent or avoid the growth of microorganisms on surfaces, it has been surprisingly found that the growth of microorganisms on surfaces can help to give surfaces the desired nature.

In an embodiment, the invention provides a method for treating a surface of a substrate, the method comprising:

a) allowing microorganisms to grow on the surface of the substrate to be treated to form a layer of microbial structures, wherein the microorganisms are selected from the group consisting of fungi, bacteria, algae, lichens, and any combination thereof; and

b) coating the microbial structure to form a first coating thereon, wherein the first coating has a thickness of not more than 1 μm.

In another embodiment, the present invention provides an article comprising a substrate, a layer of microbial structures formed on at least a portion of the surface of the substrate, and a first coating formed on the microbial structures, wherein the microbial structures comprise fungi, a structure of bacteria, algae, lichens, or any combination thereof; and wherein the first coating has a thickness of no more than 1 μm.

In a further embodiment, the invention provides an article made by using the method of the invention for treating at least a portion of the surface of a substrate of the article.

Microbes and Microbial Structures

As used herein, the term "microorganism" or its plural form "microorganisms" refers to any small or minute organism, broadly including plants and animals. It is intended as an umbrella term for a large variety of microbial organisms, including all prokaryotes, namely bacteria and archaea; and all forms of eukaryotes, including protozoa, fungi, algae, microscopic plants (green algae); and animals such as rotifers and planarians; and symbiotic associations of individual microorganisms as listed above, such as lichens.

The term "fungus" or its plural "fungi" as used herein refers to any member of a large number of eukaryotic organisms including microorganisms such as yeasts and moulds, mildews, rusts, and yeasts.

The term "algae" or its plural "algae" as used herein refers to any member of a very large and diverse group of simple, typically autotrophic organisms ranging from unicellular to multicellular forms.

As used herein, the term "lichen" or its plural form "lichens" refers to any of certain plants formed by the symbiotic combination of algae and fungi.

As used herein, the term "microbial structure" or its plural "microbial structures" refers to a structure derived from one or more microorganisms. In other words, a microbial structure is a structure formed by the growth of one or more microorganisms.

As used herein, the term "microbial structure layer" refers to a layer comprising a microbial structure or an outline of a microbial structure. In other words, the microbial structure layer may be a layer in which one or more microorganisms forming the microbial structure remain after the layer has been formed, or it may be a layer having the same profile as the microbial structure but the one or more microorganisms forming the microbial structure have been removed from cavity on which to remove.

According to the present invention, microorganisms that may be suitably used include species selected from the group consisting of fungi, bacteria, algae, lichens, and any combination thereof. These bacteria can grow on surfaces under specific conditions to form layers of microbial structures. This is advantageous because it offers the possibility to form a robust connection between the microbial structure layer and the surface. On the other hand, microbial structures generally have fine and complex micro- and nanoscale surface architectures, which are desirable for certain surface properties such as superhydrophobicity and/or superoleophobicity. The use of microorganisms as templates for the generation of superhydrophobic coatings is very novel and has not been reported before. In cases where microorganisms are used as templates, further etching or another kind of surface embodied architecture may be optional or even dispensed with.

In a particular embodiment, the microorganism is selected from fungi or bacteria comprising hyphae having a diameter between 0.3 μm and 100 μm. A hyphae is a long, branched, filamentous structure of fungi. In most fungi or bacteria, hyphae are the main mode of vegetative growth. In a preferred embodiment, the microorganisms are selected from hyphae having a diameter between 0.3 μm and 70 μm, preferably between 0.5 μm and 50 μm, more preferably between 1 μm and 25 μm, most preferably between 1.5 μm and 15 μm of fungi or bacteria. Suitably, the hyphae may have a diameter in the range between 55 μm and 100 μm or between 60 μm and 90 μm or between 0.3 μm and 40 μm or between 0.8 μm and 10 μm. The presence of hyphae enables the formation of intertwined and tangled structures that enable microscopic pockets in which air is trapped and thereby support water/oil droplets to stand on or roll off.

Suitably, the fungi or bacteria may be selected from molds, actinomycetes and any combination thereof. Examples of fungi or bacteria that may be suitably used in the present invention include, but are not limited to, Rhizopus, Mucor, Neurospora, Aspergillus, Penicillium, Streptomyces, Nocardia, Frank's Bacteria, Actinomycetes, Thermomonospora, and any combination thereof. In a particular embodiment, Streptomyces is used as the microorganism in the methods of the invention. The Streptomyces may suitably be selected from Streptomyces albicans, Streptomyces griseus, Streptomyces venezuela, Streptomyces aureus and any combination thereof.

Suitably, the algae may be selected from primitive chromophore organisms including Chlorophyta (green algae), Rhodophyta (red algae), Gray Algae, Charophyta; including long and short mastigotes (such as Diatomaceae (diatoms), Eccostinephylum, Bolidomonas, Eyespotphyceae, Phaeophyceae (brown algae), Chrysophyceae (golden algae), Cystomycetes, Xanthophyceae, and Xanthophyceae (yellow-green algae)), Cryptophyta, dinoflagellates, algal kingdoms of the dinoflagellates (vesicles); cyanobacteria (blue-green algae); and any combination thereof.

Suitably, the lichen may be selected from shrub-like, leaf-like, shell-like, scale-like, gel-like, filamentous, fibrillar, unstructured and any combination thereof.

Optionally, a growth medium or culture medium may be used as appropriate to assist the growth of microorganisms on the surface. Generally, growth media or culture media are liquids or gels designed to support the growth of microorganisms. The most common growth media used for microorganisms are nutrient broths and agar plates. Those skilled in the art will be able to select appropriate media for the particular microorganism to be used.

The microbial structure layer may have a thickness of any value that can suitably achieve the advantageous technical effects of the present invention. In a specific embodiment, the microbial structure layer may have a thickness of from 1 μm to 10 mm, preferably from 10 μm to 5 mm, more preferably from 100 μm to 3 mm, most preferably from 200 μm to 1 mm, 300 μm to 1.5 μm or from 400 μm to 2 mm or from 120 μm to 600μm thickness.

The thickness of this microbial structure layer can be tuned by the incubation time. The incubation time can be from a few minutes to several months, depending on the particular microorganism to be used. Generally, microorganisms that can form layers of microbial structures of the above thickness during a culture period of several minutes or up to 1 to 4 days will be desired. Those skilled in the art will be able to select appropriate incubation times and environmental conditions for the particular microorganism to be used.

Optionally, a step of drying the microbial structure may be performed after the desired thickness has been achieved. The drying process may last from 0.5 to 24 hours, such as 0.5 to 2 hours, 5 to 10 hours or 12 to 24 hours.

Suitably, the method of the invention may further comprise the step of deactivating or removing the microorganisms after forming the first coating. The step of deactivating or removing microorganisms, also referred to as a sterilization step, can be accomplished by applying heat, chemicals, radiation, high pressure, filtration, or any combination thereof. Thermal sterilization includes dry heat sterilization and moist heat sterilization, such as steam sterilization, autoclaving, combustion, incineration, boiling or the like. Examples of chemicals that can be used for sterilization include, but are not limited to, ethylene oxide, nitrogen dioxide, ozone, bleach, glutaraldehyde and formaldehyde solutions, phthalaldehyde, hydrogen peroxide, peracetic acid, silver, and ZnO . Radiation sterilization can use radiation such as electron beams, X-rays, gamma rays, or subatomic particles. A person skilled in the art will be able to select a suitable sterilization method for deactivating or removing microorganisms within the spirit of the present invention.

first coat

By coating the microbial structure to form a first coating thereon, the desired surface architecture can be replicated and fixed.

For the purposes of the present invention, the first coating typically has a thickness of not more than 1 μm. The thickness of the first coating can vary with the particular microorganism used and the structure of the microorganism formed thereby. In a particular embodiment, the first coating has a thickness of no more than 0.9 μm, suitably no more than 0.5 μm, more suitably no more than 0.1 μm, most suitably no more than 0.05 μm. In a particular embodiment, the first coating has a thickness of not less than 1 nm, suitably not less than 5 nm, more suitably not less than 10 nm, most suitably not less than 15 nm. The first coating may have a thickness in the range of from 8nm to 80nm, or from 12nm to 20nm, or from 30nm to 45nm, or from 60nm to 120nm. The thickness of the first coating should be such that the first coating is able to cover the microbial structure on the one hand and to replicate the surface architecture of the microbial structure on the other hand. The thickness of the first coating can be suitably selected to maximize the advantageous technical effects of the present invention.

The first coating can be formed on the microbial structure by any suitable method. For example, one or more methods selected from vapor deposition, self-propagating high temperature synthesis, thermochemical synthesis, thermal spraying, electrochemical synthesis, sol-gel methods, and in situ forming, casting may be used to form the first coating.

The material of the first coating can be organic or inorganic, assuming it can form a shell around the microbial structure. The term "shell" as used herein refers to the outer layer covering at least a portion of the microbial structure. By covering at least a portion of the microbial structure, the shell has an inner surface topology that is complementary to the surface of the microbial structure layer, and an outer surface that replicates micro- and nanoscale architecture on the surface of the microbial structure layer. The shell is preferably hard enough to be self-supporting and/or scratch-resistant so that the obtained surface topology or micro- and nanoscale architecture can be maintained in a durable manner. In certain embodiments, the shell covers all of the microbial structures in such a way that once the one or more microorganisms forming the microbial structures are removed, a cavity is formed between the substrate and the shell that has the same profile as the microbial structures.

In a particular embodiment, the first coating is an inorganic coating, such as one composed of an inorganic oxide selected from the group consisting of silicon oxide, magnesium oxide, aluminum oxide, zinc oxide, iron oxide, copper oxide, silver oxide, titanium oxide, and any combination thereof. composition.

In another particular embodiment, the first coating is an organic coating, for example consisting of a film-forming polymer or composition. Examples of film-forming polymers include, but are not limited to, cellulose-based polymers such as nitrocellulose, cellulose acetate, cellulose acetobutyrate, cellulose levulinate, and ethyl cellulose; polyurethanes; acrylic polymers; Vinyl polymers; polyvinyl butyral; alkyd resins; resins derived from aldehyde condensation products such as arylsulfonamide-formaldehyde resins, e.g. toluenesulfonamide-formaldehyde resins, arylsulfonamide-epoxy resins or ethyl toluamide resin. The film-forming composition may advantageously comprise at least one film-forming polymer, and optionally at least one auxiliary film-forming agent.

second coat

The method of the present invention may further comprise the step of forming a second coating on the first coating. The second coating may work together with the microbial structure, especially the surface architecture of the microbial structure, to provide a synergistic effect. For example, the second coating may include one or more functionalized materials such as hydrophobic, oleophobic, or amphophobic materials to provide a superhydrophobic, superoleophobic, or superamphiphobic surface. Any material including organic materials and inorganic materials having desired properties can be used for the purpose of the present invention.

In an alternative embodiment, the second coating has a surface energy of no more than 70 mJ/m ² . In a preferred embodiment, the second coating has a surface energy of not more than 60 mJ/m ² , preferably not more than 50 mJ/m ² , more preferably not more than 40 mJ/m ² , most preferably not more than 30 mJ/m ² . For the purposes of the present invention, the second coating may have as low a surface energy as possible. For example, the surface energy of the second coating may be as low as 10 mJ/m ² , 15 mJ/m ² or 20 mJ/m ² .

Examples of materials used to form the second coating include, but are not limited to, polyhexafluoropropylene (PHFP), polytetrafluoroethylene (PTFE/Teflon), fluorinated ethylene propylene (FEP), chlorotrifluoroethylene, trifluoro Vinyl chloride (Aclar), polydimethylsiloxane (silicone elastomer), fluorinated silanes such as trichloro(1H,1H,2H,2H-perfluorooctyl)silane, natural rubber, paraffin, Polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF/Tedera), polypropylene (PP), polyethylene (PE), polychlorotrifluoroethylene (PCTFE), polybutylene terephthalate (PBT), nylon-11 (polyundecylamide), sarin ionomer, polystyrene (PS), polyacrylate, polyvinyl chloride (PVC), polyvinyl alcohol (PVOH/PVAL), Polyphenylene sulfide (PPS), polyvinyl chloride (PVC), cellulose acetate (CA), polyvinylidene chloride (PVDC/Saran), polyimide (PI), polysulfone (PSU), polymethyl Methyl acrylate (PMMA), nylon-6 (polycaprolactam), polyethylene terephthalate (PET), regenerated cellulose, nylon 6/6 (polyhexamethylene adipamide), polycarbonate ( PC), polyphenylene ether (PPO), styrene-butadiene rubber, polyethersulfone, ethylene-vinyl acetate copolymer (EVA), polyurethane (PU), glass, silica, soda lime, copper, aluminum, iron, plated Tin steel and any combination thereof.

In certain embodiments, the second coating may be selected from organofluorine coatings, silicone coatings, fluorosilicon coatings, and any combination thereof.

For the purposes of the present invention, the second coating may have a thickness of not more than 2 μm. In a particular embodiment, the second coating has a thickness of no more than 1.5 μm, suitably no more than 1.0 μm, more suitably no more than 0.5 μm, most suitably no more than 0.1 μm. In a particular embodiment, the second coating has a thickness of not less than 5 nm, suitably not less than 10 nm, more suitably not less than 15 nm, most suitably not less than 20 nm. The second coating may have a thickness in the range of from 8nm to 80nm, or from 60nm to 120nm, or from 100nm to 200nm, or from 300nm to 800nm. For the purpose of maximizing the advantageous technical effects of the present invention, the thickness of the second coating layer may be appropriately selected by those skilled in the art.

The second coating can be formed by any suitable method. For example, one or more methods selected from vapor deposition, self-propagating high temperature synthesis, thermochemical synthesis, thermal spraying, electrochemical synthesis, sol-gel methods, and in situ forming, casting may be used to form the second coating.

base

Surfaces and/or substrates that may be suitably treated by the methods of the present invention may be made of any material. In an embodiment, the surface and/or substrate comprises one or more materials selected from glass, metal, ceramic, velocity, rubber and textile. In a particular embodiment, the substrate to be treated is a textile. In another particular embodiment, the substrate to be treated is glass or ceramic, optionally with a textile integrally formed on or attached to the surface of said glass or ceramic. In a further particular embodiment, the substrate to be treated is plastic or rubber, optionally with a textile integrally formed on or attached to the surface of said glass or ceramic. Preferably, the substrate has a surface roughness and/or porosity that facilitates the basis of an environment for one or more microorganisms growing on the surface of the substrate. Those skilled in the art will be able to select an appropriate surface roughness and/or porosity based on the particular microorganism being formed.

In an embodiment, the surface and/or substrate to be treated exhibits a water contact angle of less than 100° or less than 90° or less than 80° or even less than 70°.

In embodiments, the surface and/or substrate after treatment with the method of the invention exhibits a water contact angle greater than 150° or greater than 155° or greater than 160° or even greater than 165°.

In certain embodiments, the microorganisms forming the layer of microbial structures on the surface of the substrate comprise Streptomyces albicans, the first coating comprises silicon dioxide, and the second coating comprises fluorinated silanes.

For purposes of illustrating the invention, Figure 1 shows a schematic representation of an article 10 formed by the method of the invention. Article 10 includes substrate 100 , microbial structure layer 120 formed on at least a portion of surface 110 of substrate 100 , and first coating 130 formed on microbial structure 120 . A second coating layer (not shown) may be further formed on the first coating layer 130 .

application

The present invention facilitates providing desired surface topology by mimicking natural surfaces. By selecting natural surfaces with water/oil repelling properties, superhydrophobic/superoleophobic coatings can be fabricated on the surface to be treated. Superhydrophobic/superoleophobic coatings can be applied to many industrial and biological processes, such as reduction of frictional resistance, anti-icing and self-cleaning processes. Further research into the application of superhydrophobic coatings in other fields such as air and kitchen has been suggested in the art.

Specifically, the present invention may find application in at least the following: superhydrophobic/superoleophobic coating fabrication; self-cleaning materials/surfaces; waterproof but breathable materials; air purifiers; air filters; food/cosmetic storage; Lighting applications such as cooling systems for street lights; healthcare applications such as breathing masks or artificial lungs; etc.

example

The invention will be further elucidated by the following examples, which are intended to be purely illustrative of the invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification or practice of the invention disclosed herein.

I.Surface treatment

A superhydrophobic coating was formed using Streptomyces albicans on glass substrates to form microbial structures. S. albicans has a complex micro- and nanoscale surface architecture that exhibits hydrophobic properties.

Step 1: Formation of Microbial Structures

Using agar as a medium, Streptomyces albicans was cultured on the surface of a glass petri dish at room temperature (25° C.) for 3 days to form a microbial structure layer. The microbial structure layer has a thickness of about 0.5 mm.

The glass petri dish together with the cultured Streptomyces albicans was put into a vacuum desiccator to dry the surface of Streptomyces albicans at about 70° C. for about 30 minutes.

Step 2: Replication of the surface topology of the microbial structure

Ammonia-catalyzed chemical vapor deposition (CVD) of tetraethylorthosilicate (TEOS) was performed in a vacuum desiccator to deposit a _SiO2 layer on the surface of S. albicans. In this step, TEOS is hydrolyzed in the presence of ammonia solution. After hydrolysis of orthosilicate, _Si02 was formed on the surface of S. albicans. The function of the _SiO2 formed was to make a shell on top of the S. albus and to allow further superhydrophobic surface modification. The function of ammonia solution is to accelerate the hydrolysis of orthosilicate. The reaction during this step is shown in Scheme I below.

Hydrolysis reaction: Si(OC ₂ H ₅ ) ₄ +2H ₂ O→SiO ₂ +4C ₂ H ₅ OH

Scheme I. Deposition of SiO ₂ on the surface of Streptomyces albicans

The thickness of the _SiO2 layer can be tuned by the duration of CVD. In this example, the CVD treatment lasted for 24 hours and about 20 nm of _SiO2 formed around Streptomyces albicans.

Step 3: Reduce Surface Energy

The surface energy of the _SiO2 layer was reduced by another CVD treatment consisting of trichloro(1H,1H,2H,2H-perfluorooctyl)silane. The thickness of the trichloro(1H,1H,2H,2H-perfluorooctyl)silane layer obtained in this step was about 20 nm. Scheme II shows the molecular formula for trichloro(1H,1H,2H,2H-perfluorooctyl)silane.

Scheme II. Trichloro(1H,1H,2H,2H-perfluorooctyl)silane

With the aid of the above three steps, a superhydrophobic coating was obtained on the surface of the glass Petri dish.

II. Measurement

The following experiments were carried out in order to demonstrate the technical effect of the above surface treatment.

water contact angle

Figures 2a and 2b illustrate, at different magnifications, water droplets on the surface of Streptomyces albicans grown on the surface of a glass Petri dish. It can be seen that water droplets rest on the surface of Streptomyces albicans in the form of small water spheres. However, the water contact angle is less than 90°.

Figure 3a, Figure 3b and Figure 3c at different magnifications coating water droplets on the surface of the superhydrophobic coating obtained as above. It can be seen that water droplets stand on the surface of the superhydrophobic coating in the form of small water spheres and exhibit a water contact angle greater than 150°. The contact angle as derived from Figure 8c is about 150.41°.

Furthermore, as can be seen from the comparison between Figures 2a–2b and Figures 3a–3c, the synergistic effect of microbial structures and conventional surface modification methods is provided. In other words, even in cases where the microbial structure derived from Streptomyces albicans did not exhibit superhydrophobic properties, the use of the microbial structure facilitated superhydrophobicity by the hydrophobic agent trichloro(1H,1H,2H,2H-perfluorooctyl)silane. Fabrication of superhydrophobic coatings.

Therefore, the present invention provides a new method for preparing superhydrophobic coatings by roughening the surface to be treated by means of microbial structures and then reducing the surface energy of the roughened surface. To produce superhydrophobic coatings, a suitable surface structure is crucial. Previously, methods often used wet etching and machining. The present invention makes it possible to eliminate the steps of etching and machining and thus provides an easier and lower cost method for producing superhydrophobic coatings.

peel test

A peel test was performed by using an adhesive tape to demonstrate the robustness of the superhydrophobic coating obtained as above. Figure 4a shows the adhesive tape used to peel off the superhydrophobic coating and the peeling area of the superhydrophobic coating (marked in the rectangle). The peel test was performed by the following peeling operation: At room temperature (25°C), the adhesive side of the tape was brought into flat contact with the surface of the superhydrophobic coating at a pressure of 5 kg/ ^cm2 for 3 seconds, and then the tape was removed from the superhydrophobic coating. surface peeling. Repeat the same stripping operation 10 times. Water droplets were dropped on the superhydrophobic coating after each peeling operation to observe the state of the water droplets, and the superhydrophobic coating was dried in a vacuum desiccator before another peeling operation. Figures 4b, 4c and 4d show the state of water droplets on the surface of the superhydrophobic coating after 1, 5 and 10 peeling operations, respectively.

It can be seen that even after 10 peeling operations, water droplets can still stand on the surface of the superhydrophobic coating in the form of water spheres and exhibit a water contact angle greater than 150°. The superhydrophobic coatings obtained by this method are stable and robust, which provides opportunities for the wide application of superhydrophobic coatings in many fields such as self-cleaning surfaces or devices.

Scanning Electron Microscope (SEM)

The surface morphology of the superhydrophobic coating obtained above was investigated by SEM. The sample preparation is shown in Figure 5a and the results are shown at different magnifications in Figures 5b and 5c.

From Figure 5b and Figure 5c, it can be seen that a structure of intertwined and entangled monofilaments is formed on the surface of the superhydrophobic coating. Without wishing to be bound by theory, it is believed that the intertwined and tangled monofilaments make it possible to trap microscopic pockets of air within and thereby support water droplets in the form of water spheres. Monofilaments are formed by coating and replicating the hyphae present in Streptomyces albus.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the appended claims. Although the claims in this application have been tailored to particular combinations of features, it should be understood that the scope of the disclosure of the invention also includes any novel feature or any novel feature of features disclosed herein, either explicitly or implicitly. combination or any generalization thereof, whether or not it relates to the same invention as the invention presently claimed in any claim. The applicant hereby issues notice that new claims may be formulated to such features and/or combinations of features during the prosecution of this application or any further application derived therefrom.

Claims (15)

1. a kind of method for being used to handle the surface of substrate, methods described include：

A) microorganism is made to be grown on the surface of the pending substrate to form microorganism structure sheaf, wherein described micro- Biology is selected from fungi, bacterium, algae, lichens and its any combinations；With

B) the microorganism structure is coated to form first coating above, wherein the first coating has no more than 1 μm Thickness.

2. according to the method for claim 1, wherein the microorganism is selected from fungi or bacterium, the fungi or bacterium include Mycelia with the diameter between 0.3 μm and 100 μm.

3. according to the method for claim 2, wherein the fungi or bacterium are selected from selected from mould, actinomyces and its any group Close.

4. according to the method for claim 3, wherein the fungi or bacterium are selected from Rhizopus, Mucor, Neurospora Pseudomonas, Eurotium, Penicillium, streptomyces, Nocardia, Frankia, actinoplanes, high temperature monospore Pseudomonas and its any combinations.

5. according to the method for claim 4, wherein the streptomyces is in streptomyces albus, streptomyces griseus, committee Auspicious slide fastener mould, streptomyces aureofaciens and its any combinations.

6. the method according to any one of claim 1 to 5, wherein by being closed selected from vapour deposition, self propagation high temperature Into one or more of, heat chemistry synthesis, thermal spraying, electrochemistry formated, sol-gel process and formed in situ method by institute First coating is stated to be formed in the microorganism structure.

7. the method according to any one of claim 1 to 5, wherein the first coating is organic coating or inorganic painting Layer, and form the shell around the microorganism structure.

8. the method according to any one of claim 1 to 5, wherein the first coating is by selected from silica, oxygen Change magnesium, aluminum oxide, zinc oxide, iron oxide, cupric oxide, silver oxide, titanium oxide and its any combination of inorganic oxide composition Coating.

9. the method according to any one of claim 1 to 5, wherein methods described further comprise：

C) second coating is formed in the first coating.

10. according to the method for claim 9, wherein the second coating is to hate material by hydrophobic material, oleophobic material or two Expect the coating of composition, and the second coating has the surface energy no more than 70mJ/m2.

11. according to the method for claim 10, wherein the second coating is selected from organic fluorine coating, organic silicon coating, fluorine Silicon coating and its any combinations.

12. according to the method for claim 9, wherein the microorganism includes streptomyces albus, the first coating includes Silica, and the second coating includes fluorinated silane.

13. the method according to any one of claim 1 to 5, wherein methods described further comprise having been formed State the step of microorganism is deactivated or removed afterwards by first coating.

14. a kind of article (10), including substrate (100), at least a portion in the surface of the substrate (100) (110) of being formed On microorganism structure sheaf (120) and form first coating (130) on the microorganism structure (120), wherein described micro- Biological structure includes being derived from fungi, algae, lichens or its any combination of structure；And wherein described first coating, which has, not to be surpassed Cross 1 μm of thickness.

15. article (10) according to claim 14, wherein the article (10) is by using according to claim 1 to 13 Any one of at least one of method on the surface (110) for handling substrate (100) be made.